The present invention relates generally to solar energy techniques. In particular, the present invention provides a method and resulting device fabricated for solar cell structures with high efficiency and low material costs. More particularly, the present invention provides a method and resulting device for manufacturing solar cells with thin photovoltaic regions and electrical contacts coupled to the photovoltaic regions. In a particular example, electrical contacts are manufactured to position on the same side of a solar cell. Merely by way of example, the invention has been applied to solar cells and solar panels, commonly termed modules, but it would be recognized that the invention has a much broader range of applicability.
Consumption of energy resources continues to grow, as the population of the world increases rapidly to over six billion people. Often times, conventional energy comes from fossil fuels, including oil and coal, hydroelectric plants, nuclear sources, and others. As merely an example, further increases in oil consumption have been projected. Developing nations such as China and India account for most of the increase, although the United States remains the biggest consumer of energy resources. In the U.S., almost every aspect of our daily lives depends, in part, on oil. These aspects include driving to and from work, heating our homes, and operating large machines for construction and the like.
Oil is becoming increasingly scarce. As time further progresses, an era of “cheap” and plentiful oil is coming to an end. Oil will eventually disappear, which could possibly take us back to primitive times. Accordingly, other and alternative sources of energy have been developed. Modern day society has also relied upon other very useful sources of energy. Such other sources of energy include hydroelectric, nuclear, and the like to provide our electricity needs. Such electricity needs range from lighting our buildings and homes to operating computer systems and other equipment and the like. Most of our conventional electricity requirements for these home and business use come from turbines run on coal or other forms of fossil fuel, nuclear power generation plants, and hydroelectric plants, as well as other forms of renewable energy. A popular form of renewable energy has been solar, which is derived from our sun.
The sun is essential for solar energy. Solar energy possesses many desired characteristics. As noted above, solar energy is renewable. Solar energy is also abundant and clean. Conventional technologies developed often capture solar energy, concentrate it, store it, and convert it into other useful forms of energy. A popular example of one of these technologies includes solar panels. Such solar panels include solar cells that are often made using silicon bearing materials, such as polysilicon or single crystal silicon. An example of such solar cells can be manufactured by various companies that span our globe. Such companies include, among others, Q Cells in Germany, Sun Power Corporation in California, Suntech of China, and Sharp in Japan. Other companies include BP Solar and others.
Unfortunately, solar cells still have limitations although solar panels have been used successfully for certain applications. As an example, solar cells are often costly. Solar cells are often composed of silicon bearing wafer materials, which are difficult to manufacture efficiently on a large scale. Availability of solar cells made of silicon is also somewhat scarce with limited silicon manufacturing capacities. These and other limitations are described throughout the present specification, and may be described in more detail below.
From the above, it is seen that techniques for improving solar devices is highly desirable.